During the swimming season (May 1 through September 30), the maximum E. coli level shall be a geometric mean of 126 CFU per 100 ml. The geometric mean for the samples collected in the water body should not be greater than 126 CFU per 100 ml in any 30-day interval. There should not be greater than a 10% excursion frequency of 410 CFU per 100 ml for the samples collected in the same 30-day duration interval. (Fecal coliforms/100 ml) For the remainder of the year, the maximum fecal coliform level shall be a geometric mean of 2,000 CFU per 100 ml based on a minimum of five consecutive samples collected on different days during a 30-day period.

PADEP’s bacteriological assessment method states a site is ‘attaining’ when the E.coli geometric means is less than 126 CFU/100mL. A site is ‘not attaining’ when E.coli geometric mean is greater than 126CFU/100mL. A site is considered not meeting criteria when 10% of sample results are greater than 410 CFU/100mL.These sites require additional samples and information before an assessment decision is made.

Supported by a grant from the South Mountain Partnership, the Watershed Alliance tested twenty-one sites on ten Adams County streams five times during August and found that with the exception of four sites, every location tested was contaminated by E.coli at levels exceeding those recommended by the PADEP for recreational use. Recreational uses include wading, swimming, fishing, etc.

"Places like Laurel Lake where public swimming is encouraged are required to test the water to make sure it isn’t overly contaminated," said Cliff Frost, leader of the Watershed Alliance’s pathogen-testing initiative. "However, Adams County has many streams where people like to wade, fish, or swim, and most of these places aren’t tested regularly for pathogen indicators. We wanted to take a look at those stream locations to see if they were safe for recreation. We were surprised to find that most of them, at least last August, were not."

The only stream to be validated for recreational use in the News-Journal’s distribution area was Middle Creek at Strawberry Hill.

The results of Marsh Creek below Natural Dam was less than 126 CFU/100mL, but one sample was above the 410 CFU/100mL limit, which means that the PADEP and EPA would consider these waters possibly not attaining for recreational use, and further study is required to make a determination.

Toms Creek at Old Swimming Hole, Tom’s Creek at Carroll Valley Park and Marsh Creek at Sachs Coverage Bridge had geometric means between 130 and 200. These sites are considered not attaining for recreational use and impaired from pathogens.

Middle Creek near Shoops Rd., Little Marsh Creek at Iron Bridge, Marsh Creek at Lions Club Area, Toms Creek at Covered Bridge, Middle Creek at Gordon Road, Toms Creek above Mt. Hope Road Bridge, and Marsh Creek Fly Fishing Area had geometric means greater than 200, and all had at least one measurement greater than the 410 CFU/100mL limit.

These sites are clearly not attaining for recreational use and are impaired because of pathogens. Unfortunately, we observed very high recreational use by the public at several of these sites during our sampling and at other times.

The results of the Watershed Alliance study were forwarded to the PADEP for review. "Our hope is that the DEP will use our findings to inform future water-testing and treatment initiatives," said Frost.

Why test for E.coli?

E.coli is one of many different kinds of fecal coliform bacteria, and like all such bacteria occurs naturally in the digestive tract of humans and other mammals, where it aids in the digestion of food. Fecal coliform bacteria such as E.coli are also excreted in the feces of humans and other mammals, which is how they make their way into our streams and rivers. E.coli can be washed into our streams through agricultural or storm water runoff, through failing or inadequate septic systems, and through animal feces deposited directly in the stream, which happens naturally among wild animals, but is exacerbated when herd animals are allowed open access to streams.

An animal dying in a stream is another possible source of E.coli contamination downstream. It’s important to note that E.coli and other fecal coliform bacteria do not necessarily cause disease (i.e., they are not necessarily pathogenic). However, E.coli is considered an indicator bacterium because it typically occurs in association with more pathogenic organisms. Thus, the higher the E.coli levels in water, the greater the risk of humans becoming ill. (Of course, there are species of E.coli that are dangerous to varying degrees.)

Many common animal pathogens are invisible to the eye, but can cause sickness in humans, sometimes even death. Generally, these pathogens come from inside the digestive systems of animals like humans, cows, deer, etc. They get into the water mainly through feces—for example, when household septic systems fail or when farm animals are permitted to enter streams.

The usual way people become infected with these pathogens is by ingesting contaminated water. However, some pathogens can enter the bloodstream through cuts or sores on the skin. People may be infected from swimming in a polluted river or lake, especially during warm months.

The best way to avoid getting sick from contaminated water is to stay out of it, especially if you have cuts or open sores on your skin. If you do choose to enter the water, avoid getting water in your mouth, and be sure to shower after you swim, and wash your hands or use hand sanitizer before you eat.

The Watershed Alliance’s pathogen-testing project was financed in part by a grant from the Community Conservation Partnerships Program, Environmental Stewardship Fund, under the administration of the Department of Conservation and Natural Resources, Bureau of Recreation and Conservation. The grant was awarded through the South Mountain Partnership, with management oversight by the Appalachian Trail Conservancy.

The Watershed Alliance of Adams County is a partner of the South Mountain Partnership, an alliance of organizations working to preserve and enhance the cultural and natural assets of the South Mountain Landscape in Central Pennsylvania. To learn more about the South Mountain Partnership, visit SouthMountainPartnership.org.

The Watershed Alliance of Adams County is a member-supported nonprofit organization dedicated to enhancing and protecting the water resources of Adams County. For more information about the Watershed Alliance and its pathogen-testing initiative, visit AdamsWatersheds.org.

This Watershed Alliance’s pathogen-testing project was also supported by the Adams County Conservation District, Adams County Trout Unlimited, Friends of Toms Creek, and more than a dozen volunteers from the local community.

For more information on this project, including locations sampled, please visit the www.adamswatersheds.org